1. |
- Cao, Huiming, et al.
(author)
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Effect of Enterohepatic Circulation on the Accumulation of Per- and Polyfluoroalkyl Substances : Evidence from Experimental and Computational Studies
- 2022
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In: Environmental Science and Technology. - : American Chemical Society (ACS). - 0013-936X .- 1520-5851. ; 56:5, s. 3214-3224
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Journal article (peer-reviewed)abstract
- The pharmacokinetic characteristics of per- and polyfluoroalkyl substances (PFAS) affect their distribution and bioaccumulation in biological systems. The enterohepatic circulation leads to reabsorption of certain chemicals from bile back into blood and the liver and thus influences their elimination, yet its influence on PFAS bioaccumulation remains unclear. We explored the role of enterohepatic circulation in PFAS bioaccumulation by examining tissue distribution of various PFAS in wild fish and a rat model. Computational models were used to determine the reabsorbed fractions of PFAS by calculating binding affinities of PFAS for key transporter proteins of enterohepatic circulation. The results indicated that higher concentrations were observed in blood, the liver, and bile compared to other tissues for some PFAS in fish. Furthermore, exposure to a PFAS mixture on the rat model showed that the reabsorption phenomenon appeared during 8-12 h for most long-chain PFAS. Molecular docking calculations suggest that PFAS can bind to key transporter proteins via electrostatic and hydrophobic interactions. Further regression analysis adds support to the hypothesis that binding affinity of the apical sodium-dependent bile acid transporter is the most important variable to predict the human half-lives of PFAS. This study demonstrated the critical role of enterohepatic circulation in reabsorption, distribution, and accumulation of PFAS.
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2. |
- Cao, Huiming, et al.
(author)
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Screening of Potential PFOS Alternatives To Decrease Liver Bioaccumulation : Experimental and Computational Approaches
- 2019
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In: Environmental Science and Technology. - : American Chemical Society (ACS). - 0013-936X .- 1520-5851. ; 53:5, s. 2811-2819
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Journal article (peer-reviewed)abstract
- Perfluorooctanesulfonate (PFOS) is a persistent organic pollutant with significant bioaccumulation potential in liver tissues. Exposure to PFOS could cause increase of liver weight, induce adenomas of the liver, and cause hepatomegaly. Alternatives of PFOS might be designed and synthesized that have significantly lower liver bioaccumulation. In this study, we conducted animal exposure experiments to investigate tissue accumulations of 14 per- and polyfluoroalkyl substances. Correlation analysis demonstrated that accumulation of the compounds in rat liver had strong correlations with their binding affinities of liver fatty acid binding protein (LFABP). Thus, we combined a quantitative structure-activity relationship model with molecular dynamics (MD) simulations to develop computational models to predict the LFABP binding affinities of two newly synthesized alternatives, perfluorodecalin-2-sulfonic acid and N-diperfluorobutanoic acid. The binding characteristics of the PFOS alternatives for LFABP were elaborated to explore how the different structural modifications of molecules influenced the underlying binding mechanisms. Subsequent animal experiments demonstrated that the binding free energy calculations based on the MD simulations provided a good indicator to reflect the relative degree of liver accumulation of the PFOS alternatives in the same exposure doses and durations. Our findings from the combination of experimental exposure and computational model can provide helpful information to design potential alternatives of PFOS with weak LFABP binding capability and low liver accumulation.
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3. |
- Fu, Jianjie, et al.
(author)
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Temporal trends (2005-2009) of PCDD/Fs, PCBs, PBDEs in rice hulls from an e-waste dismantling area after stricter environmental regulations
- 2012
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In: Chemosphere. - : Elsevier BV. - 0045-6535 .- 1879-1298. ; 88:3, s. 330-335
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Journal article (peer-reviewed)abstract
- Primitive e-waste dismantling activities have been of increasing concern due to serious environmental and human health problems, and therefore authorities in China have strengthened the regulations on illegal e-waste recycling activities. In this work, we used rice hull as a passive sampler and investigated temporal trends of polychlorinated dibenzo-p-dioxins and dibenzofurans (PCDD/Fs), polychlorinated biphenyls (PCBs), polybrominated diphenyl ethers (PBDEs) in areas near e-waste recycling sites after the stricter regulations. Furthermore, the distribution patterns and composition profiles of these contaminants were also discussed. The average concentrations of the three groups of persistent organic pollutants (POPs) in rice hulls have markedly decreased during the period of 2005-2009. Specifically, from 12.9 (average value in 2005) to 0.37 pg WHO-TEQ/g (dry weight, dw) (in 2009) for PCDD/Fs, 47.6 (2005) to 7.10 ng g(-1)dw (2009) for PCBs, and 2.51 (2005) to 0.89 ng g(-1), dw (2009) for PBDEs. The significant decrease of combustion markers 2,3,4,7,8-PeCDF, 1,2,3,6,7,8HxCDF and PCB126, and the PCDD/PCDF ratio from 1:9 (2005) to 7:3 (2009) is likely a result of stricter regulations on open combustion activities. This study suggests that stricter control measures, strengthened laws and regulations and more environmental friendly techniques could be effective measures in reducing the release and formation of related POPs in typical e-waste dismantling sites, and these measures could further improve the quality of the environment and health of the local inhabitants.
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4. |
- Hao, Yanfen, et al.
(author)
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Air monitoring of polychlorinated biphenyls, polybrominated diphenyl ethers and organochlorine pesticides in West Antarctica during 2011-2017 : Concentrations, temporal trends and potential sources
- 2019
-
In: Environmental Pollution. - : Elsevier. - 0269-7491 .- 1873-6424. ; 249, s. 381-389
-
Journal article (peer-reviewed)abstract
- Annual air samples were collected at various sites in the Fildes Peninsula, West Antarctica from December 2010 to January 2018 using XAD-2 resin passive air samplers to investigate concentrations, temporal trends and potential sources of persistent organic pollutants (POPs) in Antarctic air. Relatively low concentrations of polychlorinated biphenyls (PCBs) (Σ19PCBs: 1.5-29.7 pg/m3), polybrominated diphenyl ethers (PBDEs) (Σ12PBDEs: 0.2-2.9 pg/m3) and organochlorine pesticides (OCPs) (Σ13OCPs: 101-278 pg/m3) were found in the atmosphere of West Antarctica. PCB-11, BDE-47 and hexachlorobenzene (HCB) were the predominant compounds in the atmosphere. The concentrations of PCBs, HCHs, DDTs and endosulfans were found to show decreasing temporal trends, whereas uniform temporal trends were observed for HCB. The atmospheric half-life values for PCBs, HCHs, DDTs and endosulfans in Antarctic air were estimated for the first time, using regressions of the natural logarithm of the concentrations versus the number of years, obtaining the values of 2.0, 2.0, 2.4 and 1.2 year, respectively. An increasing ratio of α-HCH/γ-HCH indicated long residence time for α-HCH and possible transformation of γ-HCH to α-HCH in the atmosphere. The ratios of p,p'-DDT/p,p'-DDE were mostly lower than unity in this study, which could be attributed to aged sources. It was found that long-range atmospheric transport was still considered to be the main contributing factor to the atmospheric levels of the POPs in West Antarctica whereas the contribution of human activities at the Chinese Great Wall Station was minor. The results of this study give a view on the most recent temporal trends and provide new insights regarding the occurrence of various POPs in the Antarctic atmosphere.
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5. |
- Li, Honghua, et al.
(author)
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Levels and distribution of hexabromocyclododecane (HBCD) in environmental samples near manufacturing facilities in Laizhou Bay area, East China
- 2012
-
In: Journal of Environmental Monitoring. - : Royal Society of Chemistry (RSC). - 1464-0325 .- 1464-0333. ; 14:10, s. 2591-2597
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Journal article (peer-reviewed)abstract
- A total of 55 samples including soil, sediment, plants (cypress, reed and seepweed) and aquatic species were collected at locations around hexabromocyclododecane (HBCD) manufacturing facilities in Laizhou Bay area, East China. HBCD was determined at concentrations ranging between 0.88 and 6901 ng g(-1) dry weight (dw), 2.93-1029 ng g(-1) dw, 8.88-160241 ng g(-1) dw, and 7.09-815 ng g(-1) lipid weight (lw), respectively. Significant negative correlations (r(2) = 0.54, p = 0.006) were observed between HBCD concentrations in soils and the distance from the manufacturing facility, and the concentrations became constant when the distance was >4 km. The calculation results on the bioaccumulation factors (BAFs) suggested that HBCD may be accumulated in plants. Tissue-specific bioaccumulation of HBCD diastereoisomers was found in aquatic species. For example, in crabs the highest concentrations of HBCD (815 ng g(-1) lw for female and 446 ng g(-1) lw for male) were observed in the gill. Besides the gill, α-HBCD was more preferentially accumulated in the spermary and ovary, while β- and γ-HBCD were more accumulated in the muscle. A similar distribution was also observed in roe and muscle of goby fish.
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6. |
- Li, Yingming, et al.
(author)
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Levels and vertical distributions of PCBs, PBDEs, and OCPs in the atmospheric boundary layer : observation from the Beijing 325-m meteorological tower
- 2009
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In: Environmental Science and Technology. - : American Chemical Society (ACS). - 0013-936X .- 1520-5851. ; 43:4, s. 1030-1035
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Journal article (peer-reviewed)abstract
- Polyurethane foam disk passive air sampling was carried out to investigate the levels, vertical distributions, and potential sources of polychlorinated biphenyls (PCBs), polybrominated diphenyl ethers (PBDEs) and organochlorine pesticides (OCPs) in the atmospheric boundary layer of an urban site in Asia. Sampling was performed at nine heights (15, 47, 80, 120, 160, 200, 240, 280, 320 m) of the 325-m meteorological tower in Beijing, China over three 2-month periods between December 2006 and August 2007. This is the first study to report vertical variations of PBDEs in the ABL and one of only a few studies to investigate vertical distributions of persistent organic pollutants. The levels of sigma19PCBs and sigma8PBDEs were relatively low, ranging from 22 to 65 and from 2.3 to 18 pg m-3, respectively. Air concentrations of gamma-HCH were high, with values in the range of 39-103 pg m-3 in winter, 100-180 pg m-3 in spring, and 115-242 pg m-3 in summer, respectively. alpha-HCH concentrations ranged from 20 to 86 pg m-3, p,p'-DDT between 7.3 and 78 pg m-3, and HCB between 15 and 160 pg m-3. The seasonal variations of PCBs, PBDEs, and OCPs may reflect different sources for these chemicals, such as those related with regional use (gamma-HCH), volatilization/re-emission (PBDEs, PCBs, alpha-HCH), and pesticide impurities (HCB). Although the performance reference compounds (PRCs) were spiked before deployment, the sampling rates showed strong dependency on wind speeds, resulting in large variations in uptake rates in the ABL, ranging from approximately 7.0 m3 day-1 at ground level to 11 m3 day-1 at 320 m. Levels of PCBs, PBDEs, and OCPs decreased with increasing ABL height indicating the potential of Beijing as the local sources.
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7. |
- Li, Yingming, et al.
(author)
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Reduction of atmospheric polychlorinated dibenzo-p-dioxins and dibenzofurans (PCDD/Fs) during the 2008 Beijing Olympic games
- 2011
-
In: Environmental Science and Technology. - : American Chemical Society (ACS). - 0013-936X .- 1520-5851. ; 45:8, s. 3304-3309
-
Journal article (peer-reviewed)abstract
- A total of 120 air samples were collected at three urban and one rural location in Beijing, China in the summers of 2007-2010, and before, during, and after the Beijing 2008 Olympic Games (BOG), in order to assess the effectiveness of long-term and short-term emission-control measures in reducing polychlorinated dibenzo-p-dioxins and dibenzofurans (PCDD/Fs) in the atmosphere. During the BOG (August, 2008), the PCDD/Fs concentrations decreased to an average value of 1150 fg m−3 (63 fg I-TEQ m−3), which was reduced by approximately 70% from the average in 2007 and by 29% from that in July 2008, before the Olympic event began. Although 2009-2010 levels of PCDD/Fs were significantly higher than 2008, the overall temporal trend was decreasing for summer months during the sampling campaign period. The apparent half-lives of atmospheric PCDD/Fs were estimated to be 3.2-5.8 years by statistically regressing the logarithm PCDD/Fs concentrations versus the number of years passed since 2006. The air concentrations of total suspended particulates (TSP) during the BOG ranged between 135 and 183 μg m−3, showing a 52% reduction from 2007 and 26% decrease from those prior to the Olympic event. No significant relationships were found between meteorological parameters (temperature, humidity, and wind speed) and PCDD/Fs or TSP during the BOG, whereas the PCDD/Fs concentrations were significantly dependent on the air quality (p < 0.05, positive against TSP and negative against visibility). This work is one of few temporal trend studies of atmospheric PCDD/Fs in mainland China, and provides unique insight into the effects of large-scale control measures in improving air quality and reducing one of the most ubiquitous and toxic organic pollutants in the environment.
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8. |
- Ruan, Ting, et al.
(author)
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Concentrations and composition profiles of benzotriazole UV stabilizers in municipal sewage sludge in China
- 2012
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In: Environmental Science and Technology. - : American Chemical Society (ACS). - 0013-936X .- 1520-5851. ; 46:4, s. 2071-2079
-
Journal article (peer-reviewed)abstract
- The environmental contamination and fate of benzotriazole UV stabilizers (BZTs) have received increasing attention due to their large production volume and wide usage in various consumer and industrial products. In the present work, 60 municipal sewage sludge samples from wastewater treatment plants (WWTPs) in 33 cities in China were collected to investigate the occurrence and distribution of 9 frequently used BZTs. The most dominant analogue was 2-[3,5-bis(1-methyl-1-phenylethyl)-2-hydroxyphenyl]benzotriazole (UV-234) at a median concentration of 116 ng/g (dry weight) and accounted on average for 27.2% of total BZTs. The abundance was successively followed by 2-(2-hydroxy-5-tert-octylphenyl)benzotriazole (UV-329, average 24.3%), 2-(2-hydroxy-3-tert-butyl-5-methylphenyl)-5-chlorobenzotriazole (UV-326, average 22.2%), 2-(3,5-di-tert-amyl-2-hydroxyphenyl)benzotriazole (UV-328, average 17.7%), and 2-(2-hydroxy-5-methylphenyl)benzotriazole (UV-P, average 6.6%), with median concentrations of 66.8, 67.8, 57.3, and 20.6 ng/g, respectively. 5-Chloro-2-(3,5-di-tert-butyl-2-hydroxyphenyl)benzotriazole (UV-327) and 2-(3-sec-butyl-5-tert-butyl-2-hydroxyphenyl)benzotriazole (UV-350) had low detection frequency, while 2-(3,5-di-tert-butyl-2-hydroxyphenyl)benzotriazole (UV-320) and 2-(5-tert-butyl-2-hydroxyphenyl)benzotriazole (UV-PS) were not detectable in any sample. To our knowledge, this is the first study reporting the occurrence of UV-234, UV-329, and UV-350 in sewage sludge in China. Significant correlations were found among the BZT concentrations and also with a WWTP characteristic (daily treatment volume). Furthermore, results from degradation prediction and multimedia fate simulation based on a quantitative structure-property relationship (QSPR) model at screening level also implied that the commercial BZT chemicals and their plausible transformation products might be persistent in the environment.
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9. |
- Ruan, Ting, et al.
(author)
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Identification and evaluation of a novel heterocyclic brominated flame retardant tris(2,3-dibromopropyl) isocyanurate in environmental matrices near a manufacturing plant in southern China
- 2009
-
In: Environmental Science and Technology. - : American Chemical Society (ACS). - 0013-936X .- 1520-5851. ; 43:9, s. 3080-3086
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Journal article (peer-reviewed)abstract
- A brominated flame retardant (BFR), hexabrominated heterocyclic tris-(2,3-dibromopropyl) isocyanurate (TBC), was identified,forthe first time, in the natural environment.The chemical was found in river water (2.33-163 ng/L), surface sediments (85.0 ng/g-6.03 microg/g dry weight (dw)), soils (19.6-672 ng/g dw), earthworm (9.75-78.8 ng/g dw), and carp samples (12.0-646 ng/g dw) from a factory-polluted area in southern China. It was found that TBC can strongly adsorb to organic material in sediment, and a trend of decreasing concentration with distance from the source in soil and earthworm samples, combined with calculated Kow (octanol-water partition coefficient) and Koa (octanol-air partition coefficient), suggests its potential ability to undergo regional transportation through dust deposition. Calculated results showed high Kow (log Kow = 7.37) and bioaccumulation factor (BAF) (log BAF = 4.30) of this BFR and indicate that TBC has semivolatile properties and bioaccumulation characteristic in certain biological species. Quantitative structure property relationships (QSPRs) modeling revealed that TBC has Koa (log Koa = 23.68) and Kaw (air-water partition coefficient) (log Kaw = -16.31) values several orders higher than those of other BFRs. The identification of this chemical additive further reminds us that the production and usage of heterocyclic BFRs may cause potential contamination to the surrounding environment
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10. |
- Ruan, Ting, et al.
(author)
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Presence and partitioning behavior of polyfluorinated iodine alkanes in environmental matrices around a fluorochemical manufacturing plant : another possible source for perfluorinated carboxylic acids?
- 2010
-
In: Environmental Science and Technology. - : American Chemical Society (ACS). - 0013-936X .- 1520-5851. ; 44:15, s. 5755-5761
-
Journal article (peer-reviewed)abstract
- The indistinct origins of some ubiquitous perfluorinated alkyl acids have attracted great attention in recent decades. In this present work, even-chained polyfluorinated iodides (PFIs), a group of volatile perfluorinated compounds (PFCs), including four perfluorinated iodine alkanes (FIAs) and three polyfluorinated telomer iodides (FTIs) were confirmed to be present in the environment. A wide concentration range was found for FIAs at 1.41 to 3.08x104 pg/L, and for FTIs at 1.39 to 1.32x103 pg/L in the ambient air collected around a fluorochemical manufacturing plant in Shandong province, northern China. Whereas for surface soils, most of these PFIs were below detection limits and only small amounts of analytes with higher carbon chain (such as perfluorododecyl iodide and 1H,1H,2H,2H-perfluorodecyl iodide, 16.6-499 pg/g) could be sporadically detected. The presence of the PFIs in different environmental matrices in the investigated area and calculated vapor pressures (0.095-20.4 Torr) verify that they can be considered as volatile organic chemicals and easily be released into the atmosphere. Together with reported degradation ability and long-range transport potential, the identification of these PFIs indicates that unintentional release during the telomer reaction process might also be another route for the formation and distribution of certain polyfluorinated alcohols, aldehydes, and carboxylic acid derivatives under oxidative conditions in the environment.
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11. |
- Ruan, Ting, et al.
(author)
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Trace determination of airborne polyfluorinated iodine alkanes using multisorbent thermal desorption/gas chromatography/high resolution mass spectrometry
- 2010
-
In: Journal of Chromatography A. - : Elsevier. - 0021-9673 .- 1873-3778. ; 1217:26, s. 4439-4447
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Journal article (peer-reviewed)abstract
- A novel gas chromatography/high resolution mass spectrometry method coupled with multisorbent thermal desorption cartridges has been developed for the determination of volatile neutral polyfluorinated iodine alkanes (PFIs) in airborne samples. It allows, for the first time, simultaneous analysis of four mono-iodized perfluorinated alkanes, three diiodized perfluorinated alkanes and four mono-iodized polyfluorinated telomers in ambient air samples. 3.75 L air sample was passed through a sorbent tube packed with 150 mg of Tenax TA and 200mg of Carbograph 1 TD for analyte adsorption. Important factors during the analysis procedures, such as safe sampling volume, air sampling rate, analyte desorption and transfer strategies, were optimized and good thermal desorption efficiencies were obtained. The method detection limit (MDL) concentration ranged from 0.04 pg/L for 1H,1H,2H,2H-perfluorododecyl iodide to 1.2 pg/L for perfluorohexyl iodide, and instrument response of a seven-point calibration was linear in the range of 10-1000 pg. Travel spike recoveries ranged from 83% to 116%. Small variabilities of less than 36% were obtained near the MDLs and the differences between triplicates were even smaller (2.1-7.3%) at 200 pg spiked level. The method was successfully applied to analyze ambient air samples collected near a point source, and five PFIs were identified (10.8-85.0 pg/L), with none of the analytes detectable at the background site.
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12. |
- Shang, Hongtao, et al.
(author)
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Bioaccumulation of PCDD/Fs, PCBs and PBDEs by earthworms in field soils of an E-waste dismantling area in China
- 2013
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In: Environment International. - : Elsevier. - 0160-4120 .- 1873-6750. ; 54, s. 50-58
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Journal article (peer-reviewed)abstract
- A total of 60 paired samples of earthworm, corresponding soil and wormcast were collected to investigate the bioaccumulation tendency of polychlorinated dibenzo-p-dioxins/dibenzofurans (PCDD/Fs), polychlorinated biphenyls (PCBs) and polybrominated diphenyl ethers (PBDEs) in earthworms from a typical E-waste dismantling area in east China. Significant correlations were observed for the total concentrations among different matrix types except for PCDD/Fs in soil and earthworm. The bioaccumulation tendency showed some differences among the contaminants. Calculated biota-soil accumulation factors (BSAFs) indicated that PCBs and PBDEs had higher bioaccumulation potential compared to PCDD/Fs, which was somewhat different from laboratory studies. The plot of mean BSAFs versus log Kow values for PCBs and PBDEs was well fitted by a second-order polynomial with the maximum BSAF at approximately log Kow of 6.5. While for PCDD/Fs, only a slightly decreasing trend was observed with increasing log Kow. Composition analysis indicated that tetra-, penta- and hexa-halogenated homologs had higher bioaccumulation levels, indicating that medium-halogenated congeners with log Kow around 6.5 are more easily accumulated by earthworms. Furthermore, the ratios of BDE-47/-99 and BDE-99/-100 showed some discrepancies with the technical products and other biotic species, suggesting different bioaccumulation potential of PBDEs in earthworm.
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13. |
- Wang, Ling, et al.
(author)
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Perfluorooctanesulfonate Induces Hepatomegaly and Lipoatrophy in Mice through Phosphoenolpyruvate Carboxykinase-Mediated Glyceroneogenesis Inhibition
- 2020
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In: Environmental Science and Technology Letters. - : American Chemical Society (ACS). - 2328-8930. ; 7:3, s. 185-190
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Journal article (peer-reviewed)abstract
- Perfluorooctansulfonate (PFOS) is a persistent organic pollutant that has attracted a great deal of attention due to toxic effects such as its lipid metabolism-disrupting potential. Exposure to PFOS can cause hepatomegaly and lipoatrophy in mice, but the underlying mechanisms are still unknown. Considering that glyceroneogenesis is the essential pathway for balancing the triglyceride (TG) cycle between liver and white adipose tissue (WAT), we speculate that PFOS acts via glyceroneogenesis inhibition to alter TG metabolism in the two tissues. Combining gene expression, protein expression, an enzyme activity assay, and molecular docking analysis, we report here that PFOS can interact with cytosolic phosphoenolpyruvate carboxykinase (PEPCK), the rate-limiting enzyme of glyceroneogenesis. Specifically, by repression of PEPCK, PFOS can inhibit the glyceroneogenesis process and thus decrease the glyceroneogenesis-derived glycerol level, leading to a reduced re-esterified TG level and causing atrophy in WAT. Moreover, in PFOS-exposed liver tissue, despite the fact that free glycerol and fatty acids released from WAT were being used for TG synthesis, the export of TG slowed. This eventually resulted in the continuous lipolysis of WAT and accumulation of lipid in the liver. PEPCK can be used as a key biomarker to assess the lipid metabolism disorders induced by other conventional and emerging per- and polyfluoroalkyl substances.
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14. |
- Wang, Pu, et al.
(author)
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Altitude dependence of polychlorinated biphenyls (PCBs) and polybrominated diphenyl ethers (PBDEs) in surface soil from Tibetan Plateau, China
- 2009
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In: Chemosphere. - : Elsevier. - 0045-6535 .- 1879-1298. ; 76:11, s. 1498-1504
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Journal article (peer-reviewed)abstract
- Remote mountain areas besides high latitude regions are beginning to receive increased attention in studying the transport and behavior of persistent organic pollutants (POPs). In the present work, surface soil samples were collected from the Tibetan Plateau, the highest plateau in the world which includes the northern slope of Mt. Qomolangma, to investigate the levels and trends of polychlorinated biphenyls (PCBs) and polybrominated diphenyl ethers (PBDEs) along the altitudinal gradient. The average PCB and PBDE concentrations were 185.6 ng kg-1 dry weight (dw) (range 47.1-422.6 ng kg-1 dw) and 11.1 ng kg-1 dw (range 4.3-34.9 ng kg-1 dw), respectively. Regression analysis between the log-transformed TOC-normalized concentrations and the altitudes of the sampling sites showed two opposite trends with regard to altitude dependence: negative relationship with altitude below about 4500 m followed by a positive altitude dependence above this point. Considering minimum anthropogenic activities and very sparse precipitation in the north of Himalayas, the trends above 4500 m imply that the significant altitude dependence of these two groups of POPs were irrespective of pollution sources, but could be predicted by the global distillation effect involving cold condensation in high altitude mountain areas. Increasing levels of heavier congeners were found in higher altitude sites, although the lighter congeners were the main contributors to the total amount, suggesting that less volatile congeners seem to become enriched easier than those more volatile at higher altitudes in this region.
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15. |
- Wang, Pu, et al.
(author)
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Evaluation of Soxhlet extraction, accelerated solvent extraction and microwave-assisted extraction for the determination of polychlorinated biphenyls and polybrominated diphenyl ethers in soil and fish samples
- 2010
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In: Analytica Chimica Acta. - : Elsevier. - 0003-2670 .- 1873-4324. ; 663:1, s. 43-48
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Journal article (peer-reviewed)abstract
- Three commonly applied extraction techniques for persistent organic chemicals, Soxhlet extraction (SE), accelerated solvent extraction (ASE) and microwave-assisted extraction (MAE), were applied on soil and fish samples in order to evaluate their performances. For both PCBs and PBDEs, the two more recent developed techniques (ASE and MAE) were in general capable of producing comparable extraction results as the classical SE, and even higher extraction recoveries were obtained for some PCB congeners with large octanol-water partitioning coefficients (K(ow)). This relatively uniform extraction results from ASE and MAE indicated that elevated temperature and pressure are favorable to the efficient extraction of PCBs from the solid matrices. For PBDEs, difference between the results from MAE and ASE (or SE) suggests that the MAE extraction condition needs to be carefully optimized according to the characteristics of the matrix and analyte to avoid degradation of higher brominated BDE congeners and improve the extraction yields.
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16. |
- Wang, Pu, et al.
(author)
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Temporal trends of PCBs, PCDD/Fs and PBDEs in soils from an E-waste dismantling area in East China
- 2013
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In: Environmental Science. - : Royal Society of Chemistry. - 2050-7887 .- 2050-7895. ; 15:10, s. 1897-1903
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Journal article (peer-reviewed)abstract
- The temporal trends of polychlorinated biphenyls (PCBs), polychlorinated dibenzo-p-dioxins and dibenzofurans (PCDD/Fs) and polybrominated diphenyl ethers (PBDEs) were investigated in soils from an E-waste dismantling area in East China between 2005 and 2011. Isotope dilution high resolution gas chromatography/high resolution mass spectrometry (HRGC/HRMS) was employed for the sample analysis. PCB levels declined as expected, while PCDD/Fs generally remained at a constant level during the sampling period, and PBDE concentrations tended to be slightly lower after 2007 although the decline was not statistically significant. The congener profiles indicated that lowly-halogenated congeners of these persistent organic pollutants (POPs) accounted for the decreasing levels and relative proportions of the POPs, suggesting that they have been gradually eliminated from the field soil over the years. However, the concentration levels of some heavy congeners (e.g., CB-209, OCDD and OCDF) showed different trends from those of the lighter ones. The general tendencies of the three types of POPs in soils were consistent with those reported in other studies in this area. The results implied that the enhanced regulations and centralized dismantling action introduced in 2005 might exert a limited influence on these three types of POPs in soils during the sampling period.
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17. |
- Wang, Thanh, 1979-, et al.
(author)
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Characteristic accumulation and soil penetration of polychlorinated biphenyls and polybrominated diphenyl ethers in wastewater irrigated farmlands
- 2010
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In: Chemosphere. - : Elsevier. - 0045-6535 .- 1879-1298. ; 81:8, s. 1045-1051
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Journal article (peer-reviewed)abstract
- The impact of wastewater irrigation on the distribution of two groups of persistent organic pollutants (POPs), polychlorinated biphenyls (PCBs) and polybrominated diphenyl ethers (PBDEs), in farm soil was investigated in this study. The concentrations of total analyzed PCBs were in the range 256-2140 pg g-1 on dry weight basis in surface soils. There was a higher accumulation of PCBs in farms irrigated by wastewater, with decachlorobiphenyl (CB-209) as the predominant congener. The spatial distributions of PBDEs were similar although not as obvious as that of PCBs, and BDE-209 was the predominant congener at 2040-496000 pg g-1dw, accounting for >96% of the total analyzed PBDEs. However, no significant correlations could be found between PCB and PBDE concentrations in the topsoil samples, and also with soil organic content between the different sites. On the other hand, soil vertical profiles showed significant relationship with soil organic content in cores taken from farms irrigated with wastewater. The vertical distribution was quite uniform at the topsoil, corresponding to the plowed layer, and decreased thereafter exponentially. Furthermore, the soil vertical distribution was found to be congener specific for PCBs, where less chlorinated congeners were able to penetrate deeper into the soil while heavier congeners were more restricted in their movement. This fractionation process was however not found for PBDEs. Also, the prevalence and high relative concentrations of CB-11 and CB-209 suggests that these PCB congeners should more often be included in routine environmental analysis in order to identifying unusual contamination sources.
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18. |
- Wang, Yawei, et al.
(author)
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Selection of bioindicators of polybrominated diphenyl ethers, polychlorinated biphenyls, and organochlorine pesticides in mollusks in the Chinese Bohai Sea
- 2008
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In: Environmental Science and Technology. - : American Chemical Society (ACS). - 0013-936X .- 1520-5851. ; 42:19, s. 7159-7165
-
Journal article (peer-reviewed)abstract
- Mollusks, including bivalve and gastropod samples, were collected in the summer of 2006 and 2007 to evaluate the spatial patterns of organochlorine pesticides (OCPs), polychlorinated biphenyl (PCBs), and polybrominated biphenyl ethers (PBDEs) in the coastal water of the Chinese Bohai Sea. Seven species of mollusks, including Rapana venosa (Rap), Neverita didyma (Nev), Scapharca subcrenata (Sca), Mytilus edulis (Blue mussel, Myt), Amusium (Amu), Meretix meretrix (Mer), and Crassostrea talienwhanensis (Oyster, Ost) were investigated to select appropriate bioindicators. Compared with other species, Ost and Myt possess higher lipid contents and have higher concentrations of OCPs and PBDEs. Multivariate linear regression analysis revealed that the most influential factor on the contaminant concentrations in mollusks is the trophic level (TL), followed by the lipid contents. Concentrations of OCPs, PCBs, and PBDEs correlated negatively with the TL of the selected mollusks. Results of principal component and correlation analyses suggest that Ost and Myt can be used as potential bioindicators of pollution by OCPs, PCBs, and PBDEs of the Chinese Bohai Sea.
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19. |
- Yang, Ruiqiang, et al.
(author)
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Organochlorine pesticides and PCBs in fish from lakes of the Tibetan Plateau and the implications
- 2010
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In: Environmental Pollution. - : Elsevier BV. - 0269-7491 .- 1873-6424. ; 158:6, s. 2310-6
-
Journal article (peer-reviewed)abstract
- High mountains may play significant roles in the global transport of persistent organic pollutants (POPs). This work aims to investigate the levels, patterns and distribution of semi-volatile organochlorine pollutants and to improve the understanding of the long-range atmospheric transport and fate of contaminants on the Tibetan Plateau. A total of 60 fish samples were collected from eight lakes located between 2813 and 4718 m above sea level across the Plateau. Concentrations of polychlorinated biphenyls (PCBs), organochlorine pesticides (OCPs) including dichlorodiphenyltrichloroethane and its metabolites (DDTs), hexachlorocyclohexanes (HCHs) and hexachlorobenzene (HCB) were measured in fish muscle. The results showed that concentrations of DDT, HCH and HCB were comparable to or lower than those found in remote mountains of Europe, Canada and US, while PCB concentrations in fish were, on average, about 4-150 times lower on Tibet than at other mountain areas. The transport and fate of contaminants in the Plateau are significantly influenced by the unique climatological and meteorological conditions, particularly by the summer Indian monsoon and winter westerly jet stream.
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20. |
- Zeng, Lixi, et al.
(author)
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Distribution and trophic transfer of short-chain chlorinated paraffins in an aquatic ecosystem receiving effluents from a sewage treatment plant
- 2011
-
In: Environmental Science and Technology. - Washington, USA : American Chemical Society (ACS). - 0013-936X .- 1520-5851. ; 45:13, s. 5529-5535
-
Journal article (peer-reviewed)abstract
- Short-chain chlorinated paraffins (SCCPs) are an extremely complex group of industrial chemicals and found to be potential persistent organic pollutants (POPs), and thus have attracted extensive concern worldwide. In this study, influent, effluent, and sludge were collected from a large sewage treatment plant (STP) in Beijing, China. Water, sediment, and aquatic species were also collected from a recipient lake that receives effluents discharged from the STP. These samples were then analyzed to investigate the effect of STP effluent on distribution and trophic transfer of SCCPs in the local aquatic ecosystem. Concentrations of total SCCPs (ΣSCCPs) in lake water and surface sediments were found in the range 162-176 ng/L and 1.1-8.7 μg/g (dry weight, dw), respectively. Vertical concentration profiles of sediment cores showed ΣSCCPs decreased exponentially with increasing depth. Specific congener composition analysis in sediment layers indicated possible in situ biodegradation might be occurring. High bioaccumulation of SCCPs was observed in the sampled aquatic species. The bioaccumulation factor (BAF) generally increased with the number of chlorines in the SCCP congeners. A significantly positive correlation between lipid-normalized ΣSCCPs concentration and trophic levels (R(2) = 0.65, p < 0.05) indicate that SCCPs can biomagnify through the food chain in the effluent-receiving aquatic ecosystem.
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21. |
- Zhang, Haidong, et al.
(author)
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Assessment on the occupational exposure of manufacturing workers to Dechlorane Plus through blood and hair analysis
- 2013
-
In: Environmental Science and Technology. - : American Chemical Society (ACS). - 0013-936X .- 1520-5851. ; 47:18, s. 10567-10573
-
Journal article (peer-reviewed)abstract
- Dechlorane Plus (DP), as a widely used flame retardant in different electrical and textile applications, has recently attracted great concern around the world. The present study investigated the DP levels and distribution in human samples from a DP manufacturing plant and a nearby area in east China. The DP concentrations ranged from 89.8 to 2958 ng/g lipid weight in whole blood and 4.08 to 2159 ng/g dry weight in hair. For the workers engaged in DP manufacturing process, their DP levels were significantly higher than those in most of the other two control groups from the nearby area. The values of anti-DP fractional abundance (fanti ratio) were commonly lower in the human samples from both the manufacturing plant and nearby area compared with those in the commercial products, and excretion as well as biotransformation are possible reasons for stereoselective accumulation of the syn-DP isomer in humans. Furthermore, a significantly positive relationship (p < 0.05) was obtained between (i) the concentrations (and fanti) in the paired blood and hair samples, indicating a similar distribution pattern of the two DP isomers in the paired samples; (ii) the DP levels in human body and the exposure time (p < 0.05), which suggests that further assessment could be needed to investigate potential long-term risks to the occupational population.
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22. |
- Zhu, Nali, et al.
(author)
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Tris(2,3-dibromopropyl) isocyanurate, hexabromocyclododecanes, and polybrominated diphenyl ethers in mollusks from Chinese Bohai Sea.
- 2012
-
In: Environmental Science and Technology. - Washington DC, USA : American Chemical Society (ACS). - 0013-936X .- 1520-5851. ; 46:13, s. 7174-7181
-
Journal article (peer-reviewed)abstract
- A novel brominated flame retardant (BFR), tris(2,3-dibromopropyl) isocyanurate (TBC), as well as hexabromocyclododecanes (HBCDs) and polybrominated diphenyl ethers (PBDEs), were analyzed in 11 species of mollusks collected from nine coastal cities around the Chinese Bohai Sea in 2009 and 2010. The detection frequencies were 100%, 99%, and 77% for PBDEs, HBCDs, and TBC, respectively. Concentrations of ∑HBCDs ranged from below detection limit (nd) to 28.8 ng g(-1) on a dry weight (dw) basis, followed by ∑(12)PBDE (0.01-20.4 ng g(-1) dw) and TBC (nd-12.1 ng g(-1) dw). Statistically significant linear correlations were found among the three BFRs. Positive correlations were found between BFRs concentrations and lipid content in mollusks. The concentrations tend to decrease with increasing trophic levels of the mollusks, implying trophic dilution rather than biomagnifications of the BFRs in the aquatic food chains of the sampling area. Among the 11 mollusks species, Mytilus edulis showed higher bioaccumulation capability than others and was therefore considered to be an appropriate bioindicator of contamination by the BFRs in the Chinese Bohai Sea, in agreement with its previous selection for the biomonitoring of organochlorine pesticides (OCPs) and polychlorinated biphenyls (PCBs). A dramatic decrease in PBDE concentrations in mollusks of the area was found for the time period from 2003 to 2010, with a half-life of only 2.3 ± 1.7 years, reflecting a rapid response of mollusks to the change in pollution of the marine environment.
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23. |
- Fu, Jianjie, et al.
(author)
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Elevated levels of perfluoroalkyl acids in family members of occupationally exposed workers : the importance of dust transfer
- 2015
-
In: Scientific Reports. - : Nature Publishing Group. - 2045-2322. ; 5
-
Journal article (peer-reviewed)abstract
- The exposure pathways of perfluoroalkyl acids (PFAAs) to humans are still not clear because of the complex living environment, and few studies have simultaneously investigated the bioaccumulative behaviour of different PFAAs in humans. In this study, serum, dust, duplicate diet, and other matrices were collected around a manufacturing plant in China, and homologous series of PFAAs were analysed. PFAA levels in dust and serum of local residents in this area were considerably higher than those in non-polluted area. Although dietary intake was the major exposure pathway in the present study, dust ingestion played an important role in this case. Serum PFAAs in local residents was significantly correlated with dust PFAAs levels in their living or working microenvironment. Serum PFAAs and dust PFAAs were significantly higher in family members of occupational workers (FM) than in ordinary residents (OR) (p<0.01). After a careful analysis of the PFAAs exposure pathway, a potential pathway in addition to direct dust ingestion was suggested: PFAAs might transferred from occupational worker's clothes to dinners via cooking processes. The bioaccumulative potential of PFHxS and PFOS were higher than other PFAAs, which suggested a substantial difference between the bioaccumulative ability of perfluorinated sulfonic acids and perfluorinated carboxylic acids.
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24. |
- Fu, Jianjie, et al.
(author)
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Influence of e-waste dismantling and its regulations : temporal trend, spatial distribution of heavy metals in rice grains, and its potential health risk
- 2013
-
In: Environmental Science and Technology. - : American Chemical Society (ACS). - 0013-936X .- 1520-5851. ; 47:13, s. 7437-7445
-
Journal article (peer-reviewed)abstract
- Enhanced regulations, centralized dismantling processes, and sophisticated recycling technologies have been implemented in some e-waste dismantling areas in China with regard to environmental and economic aspects since 2005. In this study, rice grain samples were collected from 2006 to 2010 in an e-waste dismantling area to investigate the temporal trends and spatial distribution of As, Cd, Cu, and Pb. Geometric means of As, Cd, Cu, and Pb in rice samples from the e-waste dismantling area were 111, 217, 4676, and 237 ng g(-1), respectively. Levels of Pb showed a significant decreasing trend during the sampling period, whereas the other three elements remained relatively constant or even increased. Concentrations of Cd, Cu, and Pb in the e-waste dismantling area were significantly higher than those in the non-e-waste dismantling area (p < 0.05), which showed a close connection between e-waste dismantling activities and elevated Pb, Cu, and Cd contents. Risk assessment for human via rice consumption indicated that over 60% of the hazard quotient of Cd exceeded 1 in the e-waste dismantling area. Our study implied that stricter implementation of regulatory measures might lead to positive effects in controlling the release of some heavy metals to the environment. However, environmental behaviors differed with geochemical characteristics of individual elements. Further remediation actions to reduce heavy metal pollution to the surrounding environment might still be needed.
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25. |
- Fu, Jianjie, et al.
(author)
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Spatial distribution of polychlorinated biphenyls (PCBs) and polybrominated biphenyl ethers (PBDEs) in an e-waste dismantling region in Southeast China : use of apple snail (Ampullariidae) as a bioindicator
- 2011
-
In: Chemosphere. - : Elsevier BV. - 0045-6535 .- 1879-1298. ; 82:5, s. 648-655
-
Journal article (peer-reviewed)abstract
- Fengjiang is a large e-waste dismantling site located in southeast China. In this paper, apple snail and soil samples were collected from this e-waste dismantling site and 25 vicinal towns to investigate the contamination status, spatial distributions and congener patterns of polychlorinated biphenyls (PCBs) and polybrominated biphenyl ethers (PBDEs). Total PCB concentrations in apple snails (3.78-1812ngg(-1) dry weight (dw)) were significant higher than that in soil samples (0.48-90.1ngg(-1) dw). PBDE (excluding BDE 209) concentrations in apple snail and soil samples ranged from 0.09 to 27.7ngg(-1) dw and 0.06 to 31.2ngg(-1) dw, respectively. Concentrations of PCBs and PBDEs in snails and soils correlated negatively with the distance from Fengjiang. Both the concentrations and profiles of the pollutants were significantly correlated (p<0.05) between the snail and soil samples, indicating the suitability of apple snail as a reliable bioindicator for PCBs and PBDEs contamination in this region. Relatively high concentrations of PCBs and PBDEs at locations far from e-waste dismantling sites implied that these pollutants have been transported to surrounding regions.
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26. |
- Gao, Yan, et al.
(author)
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Differential accumulation and elimination behavior of perfluoroalkyl acid isomers in occupational workers in a manufactory in China
- 2015
-
In: Environmental Science and Technology. - : American Chemical Society (ACS). - 0013-936X .- 1520-5851. ; 49:11, s. 6953-6962
-
Journal article (peer-reviewed)abstract
- In this study, serum and urine samples were collected from 36 occupational workers in a fluorochemical manufacturing plant in China from 2008 to 2012 to evaluate the body burden and possible elimination of linear and branched perfluoroalkyl acids (PFAAs). Indoor dust, total suspended particles (TSP), diet, and drinking water samples were also collected to trace the occupational exposure pathway to PFAA isomers. The geometric mean concentrations of perfluorooctanesulfonate (PFOS), perfluorooctanoate (PFOA), and perfluorohexanesulfonate (PFHxS) isomers in the serum were 1386, 371, and 863 ng mL(-1), respectively. The linear isomer of PFOS, PFOA, and PFHxS was the most predominant PFAA in the serum, with mean proportions of 63.3, 91.1, and 92.7% respectively, which were higher than the proportions in urine. The most important exposure routes to PFAA isomers in the occupational workers were considered to be the intake of indoor dust and TSP. A renal clearance estimation indicated that branched PFAA isomers had a higher renal clearance rate than did the corresponding linear isomers. Molecular docking modeling implied that linear PFOS (n-PFOS) had a stronger interaction with human serum albumin (HSA) than branched isomers did, which could decrease the proportion of n-PFOS in the blood of humans via the transport of HSA.
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27. |
- GuangBo, Qu, et al.
(author)
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Detection of tris-(2,3-dibromopropyl) isocyanurate as a neuronal toxicant in environmental samples using neuronal toxicity-directed analysis
- 2011
-
In: Science in China Series B. - : Science Press. - 1674-7291 .- 1869-1870. ; 54:10, s. 1651-1658
-
Journal article (peer-reviewed)abstract
- Neuronal toxic pollutants in environment possess hazards to human health. It is essential to determine the causative neuronal toxicants in environmental samples. In the present study, viability of primary cultured cerebellar granule neurons (CGNs), combined with sample extraction, chemical fractionation and identification, was applied for screening acid-resistant neuronal toxic substances in environmental samples. River sediments and agricultural soils along the river near a brominated flame retardant (BFR) manufacturing plant in South China were collected to screen the key neuronal toxicants. The results indicated that the manufacturing plant was a source of neuronal toxicity risks. In the sediment and soil near the plant, one of the causative toxicants was identified as tris-(2,3-dibromopropyl) isocyanurate (TBC) using HPLC-MS/MS. In addition, an unknown chemical possibly causing significant neuronal toxicity was isolated from all the soil samples in the region.
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28. |
- Hao, Yanfen, et al.
(author)
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Distribution, seasonal variation and inhalation risks of polychlorinated dibenzo-p-dioxins and dibenzofurans, polychlorinated biphenyls and polybrominated diphenyl ethers in the atmosphere of Beijing, China
- 2018
-
In: Environmental Geochemistry and Health. - : Springer Netherlands. - 0269-4042 .- 1573-2983. ; 40:5, s. 1907-1918
-
Journal article (peer-reviewed)abstract
- Spatial distribution, seasonal variation and potential inhalation risks of polychlorinated dibenzo-p-dioxins and dibenzofurans (PCDD/Fs), polychlorinated biphenyls (PCBs) and polybrominated diphenyl ethers (PBDEs) were investigated in the atmosphere of Beijing, using passive air samplers equipped with polyurethane foam disks. Concentrations of ΣPCDD/Fs, ΣPCBs and ΣPBDEs ranged from 8.4 to 179 fg WHO2005-TEQ/m(3), 38.6-139 and 1.5-176 pg/m(3), respectively. PCDFs showed higher air concentrations than those of PCDDs, indicating the influence of industrial activities and other combustion processes. The non-Aroclor congener, PCB-11, was detected in air (12.3-99.4 pg/m(3)) and dominated the PCB congener profiles (61.7-71.5% to ∑PCBs). The congener patterns of PBDEs showed signatures from both penta-BDE and octa-BDE products. Levels of PCDD/Fs, PCBs and PBDEs at the industrial and residential sites were higher than those at rural site, indicating human activities in urban area as potential sources. Higher air concentrations of PCDD/Fs, PCBs and PBDEs were observed in summer, which could be associated with atmospheric deposition process, re-volatilization from soil surface and volatilization from use of technical products, respectively. Results of inhalation exposure and cancer risk showed that atmospheric PCDD/Fs, dioxin-like PCBs and PBDEs did not cause high risks to the local residents of Beijing. This study provides further aid in evaluating emission sources, influencing factors and potential inhalation risks of the persistent organic pollutants to human health in mega-cities of China.
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29. |
- Hou, Qihui, et al.
(author)
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Detection of bioavailable cadmium, lead, and arsenic in polluted soil by tailored multiple Escherichia coli whole-cell sensor set
- 2015
-
In: Analytical and Bioanalytical Chemistry. - : Springer Berlin/Heidelberg. - 1618-2642 .- 1618-2650. ; 407:22, s. 6865-6871
-
Journal article (peer-reviewed)abstract
- Microbial whole-cell sensor has been widely used to assess bioavailability and risk of toxic elements, but their environmental use is still limited due to the presence of other interfering pollutants and the nonspecific binding in cells, which leads to inaccurate results. Here, we proposed a strategy combining Escherichia coli sensor set with binary regression models for the specific detection of bioavailable cadmium (Cd), lead (Pb), and arsenic (As) in a co-polluted environment. Initial tests suggested that the sensor set respectively termed pcadCluc, pzntRluc, and parsRluc could be classified into two groups according to their specific response to Cd, Pb, and As: group 1 (pcadCluc and pzntRluc) induced by a Cd-Pb mix and group 2 (parsRluc) induced by a Cd-As mix. Based on the variance in responses of each sensor to mixtures of target elements, three binary linear equations for two sensor groups were set up to calculate the individual concentrations in the mixture solutions. This method was then used to quantify the bioavailable Cd, Pb, and As in soils from a co-polluted mining region and to compare the results with other methods. Results showed that the conventional single target sensor method overestimated the bioavailability of each element, while sensor set was credible for accurate bioavailable Cd, Pb, and As quantification and comparable with the results from inductively coupled plasma mass spectrometry (ICP-MS) analysis. Our method can potentially be extended to cover the specific detection of other bioavailable toxic elements in different environmental settings.
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30. |
- Hu, Yuning, et al.
(author)
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Cooking methods affect the intake of per- and polyfluoroalkyl substances (PFASs) from grass carp
- 2020
-
In: Ecotoxicology and Environmental Safety. - : Academia Press. - 0147-6513 .- 1090-2414. ; 203
-
Journal article (peer-reviewed)abstract
- Consumption of fish is one of the predominant sources of human exposure to per- and polyfluoroalkyl substances (PFASs). In this study, the effect of various cooking methods (boiling, steaming, grilling and frying) on the levels of PFASs in fish muscle and the intake of PFASs was explored by using grass carp collected from Tangxun Lake, Wuhan, China. Perfluorooctane sulfonate (PFOS) was the predominant PFASs in raw fish fillets, with the concentrations ranging from 59.6 to 136 ng/g ww, followed by perfluorobutane sulfonate (PFBS) (7.73-51.9 ng/g ww). The concentrations of long-chain PFASs in fish increased after cooking, while those of short-chain PFASs decreased. The amounts of PFASs in the cooked fish fillets decreased except PFOS. Short-chain PFASs, including PFBS and perfluoroheptanoic acid (PFHpA), were dominant in cooking juice. The highest amounts of PFBS in the juices were observed after boiling and frying, even higher than those in cooked fish fillets, suggesting that the release of short-chain PFASs to the cooking juices could not be neglected. Based on these results, the intake of short-chain PFASs amount through cooked fish fillets slightly decreased, but the intake of PFOS amount increased. However, consumption of cooking juice (fish soup) could increase the exposure risk of PFBS. Comprehensively considering the increase of PFOS and decrease of total PFASs, boiling may be the relatively better method to cook fish. As PFASs are ubiquitous and inevitable in aquatic food, it is thus important to choose appropriate cooking processes and dietary habits for reducing the intake of different PFASs from fish.
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31. |
- Li, Juan, et al.
(author)
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Plasmid-mediated quinolone resistance genes and antibiotic residues in wastewater and soil adjacent to swine feedlots : potential transfer to agricultural lands
- 2012
-
In: Journal of Environmental Health Perspectives. - : National Institute of Environmental Health Science. - 0091-6765 .- 1552-9924. ; 120:8, s. 1144-1149
-
Journal article (peer-reviewed)abstract
- BACKGROUND: Inappropriate use of antibiotics in swine feed could cause accelerated emergence of antibiotic resistance genes, and agricultural application of swine waste could spread antibiotic resistance genes to the surrounding environment.OBJECTIVES: We investigated the distribution of plasmid-mediated quinolone resistance (PMQR) genes from swine feedlots and their surrounding environment.METHODS: We used a culture-independent method to identify PMQR genes and estimate their levels in wastewater from seven swine feedlot operations and corresponding wastewater-irrigated farm fields. Concentrations of (fluoro)quinolones in wastewater and soil samples were determined by ultra-performance liquid chromatography-electrospray tandem mass spectrometry.RESULTS: The predominant PMQR genes in both the wastewater and soil samples were qnrD, qepA, and oqxB, whereas qnrS and oqxA were present only in wastewater samples. Absolute concentrations of all PMQR genes combined ranged from 1.66 × 107 to 4.06 × 108 copies/mL in wastewater and 4.06 × 106 to 9.52 × 107 copies/g in soil. Concentrations of (fluoro)quinolones ranged from 4.57 to 321 ng/mL in wastewater and below detection limit to 23.4 ng/g in soil. Significant correlations were found between the relative abundance of PMQR genes and (fluoro)quinolone concentrations (r = 0.71, p = 0.005) and the relative abundance of PMQR genes in paired wastewater and agricultural soil samples (r = 0.91, p = 0.005).CONCLUSIONS: Swine feedlot wastewater may be a source of PMQR genes that could facilitate the spread of antibiotic resistance. To our knowledge, this is the first study to examine the occurrence of PMQR genes in animal husbandry environments using a culture-independent method.
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32. |
- Li, Yingming, et al.
(author)
-
Atmospheric distribution of polychlorinated dibenzo-p-dioxins, dibenzofurans and dioxin-like polychlorinated biphenyls around a steel plant area, northeast China
- 2010
-
In: Chemosphere. - : Elsevier BV. - 0045-6535 .- 1879-1298. ; 79:3, s. 253-258
-
Journal article (peer-reviewed)abstract
- Air monitoring of polychlorinated dibenzo-p-dioxins (PCDDs), polychlorinated dibenzofurans (PCDFs), and dioxin-like polychlorinated biphenyls (PCBs) was carried out in June 2008 and January 2009 to investigate the concentrations, profiles and estimating potential inhalation risks to the local residents around a steel plant area in northeast China. The air concentrations and WHO-TEQs of PCDD/Fs ranged 94-4944fgm(-3) (average 1352fgm(-3)) and 3-247fgm(-3) (average 81fgm(-3)), respectively. The WHO-TEQ concentrations of dioxin-like PCBs ranged 1-18fgm(-3) (average 5fgm(-3)), contributing to 3.6-26% of the total TEQ. Higher PCDD/F concentrations were observed in the winter, whereas higher dioxin-like PCB concentrations were found in the summer. The seasonal trend can be related to the significant correlation between the concentrations of dioxins and the reciprocal of temperature (positive for PCDD/Fs, P<0.01; negative for dioxin-like PCBs, P=0.05). A significant positive correlation (P<0.0001) was found between the concentration of total suspended particulate (TSP) and PCDD/F concentrations, but not for PCB congeners. Although the steel plant sites showed higher dioxin levels than the residential and background areas, the PCDD/F levels in the atmosphere of the steel plant area was at a relatively low level. The results from this study provides further aid in evaluating the impact of steel plants as PCDD/Fs emission sources to the ambient air in China.
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33. |
- Li, Yongting, et al.
(author)
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Organophosphate Flame Retardants in Pregnant Women : Sources, Occurrence, and Potential Risks to Pregnancy Outcomes
- 2023
-
In: Environmental Science and Technology. - : American Chemical Society (ACS). - 0013-936X .- 1520-5851. ; 57:18, s. 7109-7128
-
Research review (peer-reviewed)abstract
- Organophosphate flame retardants (OPFRs) are found in various environmental matrixes and human samples. Exposure to OPFRs during gestation may interfere with pregnancy, for example, inducing maternal oxidative stress and maternal hypertension during pregnancy, interfering maternal and fetal thyroid hormone secretion and fetal neurodevelopment, and causing fetal metabolic abnormalities. However, the consequences of OPFR exposure on pregnant women, impact on mother-to-child transmission of OPFRs, and harmful effects on fetal and pregnancy outcomes have not been evaluated. This review describes the exposure to OPFRs in pregnant women worldwide, based on metabolites of OPFRs (mOPs) in urine for prenatal exposure and OPFRs in breast milk for postnatal exposure. Predictors of maternal exposure to OPFRs and variability of mOPs in urine have been discussed. Mother-to-child transmission pathways of OPFRs have been scrutinized, considering the levels of OPFRs and their metabolites in amniotic fluid, placenta, deciduae, chorionic villi, and cord blood. The results showed that bis(1,3-dichloro-2-propyl) phosphate (BDCIPP) and diphenyl phosphate (DPHP) were the two predominant mOPs in urine, with detection frequencies of >90%. The estimated daily intake (EDIM) indicates low risk when infants are exposed to OPFRs from breast milk. Furthermore, higher exposure levels of OPFRs in pregnant women may increase the risk of adverse pregnancy outcomes and influence the developmental behavior of infants. This review summarizes the knowledge gaps of OPFRs in pregnant women and highlights the crucial steps for assessing health risks in susceptible populations, such as pregnant women and fetuses.
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34. |
- Li, Yingming, et al.
(author)
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Study of PCBs and PBDEs in King George Island, Antarctica, using PUF passive air sampling
- 2012
-
In: Atmospheric Environment. - : Elsevier. - 1352-2310 .- 1873-2844. ; 51, s. 140-145
-
Journal article (peer-reviewed)abstract
- Polyurethane foam (PUF)-disk based passive air samplers were deployed in King George Island, Antarctica, during the austral summer of 2009-2010, to investigate levels, distributions and potential sources of polychlorinated biphenyls (PCBs) and polybrominated diphenyl ethers (PBDEs) in Antarctic air. The atmospheric levels of Sigma indicator PCBs and Sigma(14) PBDEs ranged from 1.66 to 6.50 pg m(-3) and from 0.67 to 2.98 pg m(-3), respectively. PCBs homologue profiles were dominated by di-PCBs, tri-PCBs and tetra-PCBs, whereas BDE-17 and BDE-28 were the predominant congeners of PBDEs, which could be explained by long-range atmospheric transport processes. However, the sampling sites close to the Antarctic research stations showed higher atmospheric concentrations of PCBs and PBDEs than the other sites, reflecting potential local sources from the Antarctic research stations. The non-Aroclor congener PCB-11 was found in all the air samples, with air concentrations of 3.60-31.4 pg m(-3) (average 15.2 pg m(-3)). Comparison between the results derived from PUF-disk passive air sampling and high-volume air sampling validates the feasibility of using the passive air samplers in Antarctic air. To our knowledge, this study is the first employment of PUF-disk based passive air samplers in Antarctic atmosphere.
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35. |
- Li, Zhuona, et al.
(author)
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Effects of polycyclic musks HHCB and AHTN on steroidogenesis in H295R cells
- 2013
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In: Chemosphere. - : Elsevier. - 0045-6535 .- 1879-1298. ; 90:3, s. 1227-1235
-
Journal article (peer-reviewed)abstract
- 1,3,4,6,7,8-Hexahydro-4,6,6,7,8,8-hexamethylcyclopenta-(γ)-2-benzopyran (HHCB) and 7-acetyl-1,1,3,4,4,6-hexamethyl-1,2,3,4-tetrahydronaphthalene (AHTN) are widely used in personal care products. Previous studies showed that HHCB and AHTN can be found in various environmental matrices and have potential endocrine disrupting effects. However, the effects on adrenocortical function of HHCB and AHTN are not fully understood. This study evaluated the influences of HHCB and AHTN on seven steroid hormones (progesterone, aldosterone, cortisol, 17α-OH-progesterone, androstenedione, 17β-estradiol, and testosterone) and 10 genes involved in steroidogenic pathways (HMGR, StAR, CYP11A1, 3βHSD2, CYP17, CYP21, CYP11B1, CYP11B2, 17βHSD, and CYP19) using the H295R cell line in the absence and presence of 8-Br-cAMP. MC2R transcription on the cell membrane was also examined to further investigate the effects of HHCB and AHTN on adrenal steroidogenesis. The results demonstrated that HHCB and AHTN could inhibit progesterone and cortisol production mainly by the suppression of 3βHSD2 and CYP21. Meanwhile, high concentrations of AHTN can affect the sensitivity of H295R cells to ACTH by disrupting MC2R transcription. Overall, the results indicate that high concentrations of HHCB and AHTN can affect steroidogenesis in vitro using the H295R cell line.
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36. |
- Qu, Guangbo, et al.
(author)
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Identification of tetrabromobisphenol A diallyl ether as an emerging neurotoxicant in environmental samples by bioassay-directed fractionation and HPLC-APCI-MS/MS
- 2011
-
In: Environmental Science and Technology. - : American Chemical Society (ACS). - 0013-936X .- 1520-5851. ; 45:11, s. 5009-5016
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Journal article (peer-reviewed)abstract
- Brominated flame retardants (BFRs) have been widely used as additives in products to reduce their flammability. Recent findings suggested that some BFRs exhibit neurotoxicity and thus might pose a threat to human health. In this work, a neurotoxicity assay-directed analysis was developed, combining sample cleanup, fractionation, chemical identification, and bioassay. Viability of primary cultured cerebellar granule neurons (CGNs) was used to evaluate the neurotoxicity of extracts or separated fractions from environmental samples. Tetrabromobisphenol A diallyl ether (TBBPA DAE) was identified as the causative toxicant in sediment samples collected from a river near a brominated flame retardant (BFR) manufacturing plant in South China. Liquid chromatography atmospheric pressure chemical ionization tandem mass spectrometry (LC-APCI-MS/MS) was optimized to determine TBBPA DAE levels in the potent fractions and to confirm TBBPA DAE as the key neurotoxicant. On the basis of comparison with the structure of other TBBPA derivatives, the 1-propenyl group in TBBPA DAE appears to be the cause for the neurotoxic potency. The levels of TBBPA DAE in samples along the river were found at up to 49 ng/L for river water, 10,183 ng/g dry weight (dw) in surface sediments, and 42 ng/g dw in soils. According to the distribution of TBBPA DAE in the environmental samples, the manufacturing plant was identified as the release source of TBBPA DAE. To our knowledge, this study is the first to demonstrate potential neurotoxicity induced by TBBPA DAE in real environmental samples.
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37. |
- Shang, Hongtao, et al.
(author)
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The presence of polychlorinated biphenyls in yellow pigment products in China with emphasis on 3,3'-dichlorobiphenyl (PCB 11)
- 2014
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In: Chemosphere. - : Elsevier. - 0045-6535 .- 1879-1298. ; 98, s. 44-50
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Journal article (peer-reviewed)abstract
- A non-Aroclor PCB congener, 3,3'-dichlorobiphenyl (PCB 11) has recently attracted wide concerns because of its environmental ubiquity and specific sources potentially associated with yellow pigment production. In order to investigate PCB 11 and other PCBs in the yellow pigment products, 24 yellow pigment samples were collected from three different manufacturing plants in China. ∑20PCBs and PCB 11 were in the range of 50.7-9.19×10(5) ng g−1 and 41.7-9.18×105 ng g−1, respectively, which was much higher than those reported in previous study. The corresponding TEQ values ranged between 0.16 and 4.21×103 ng WHO2005-TEQ kg−1. The contribution of PCB 11 to ∑20PCBs reached up to 85.5% (median value) followed by PCB 28, PCB 77, and PCB 52 with contributions of 10.5%, 6.70%, and 5.40%, respectively. Significant differences were observed for PCB 11 concentrations among the different types of yellow pigment from the same plant and among the same sample types from different plants. The PCB 11 concentrations in diarylide yellow pigments produced from 3,3'-dichlorbenzidine were the highest in all the samples. It demonstrates that yellow pigment is a significant source not only for the widespread pollution of PCB 11 but also for other PCBs, especially for the lower chlorinated congeners.
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38. |
- Sun, Jianteng, et al.
(author)
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Hydroxylated polybrominated diphenyl ethers (OH-PBDEs) in biosolids from municipal wastewater treatment plants in China
- 2013
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In: Chemosphere. - : Elsevier. - 0045-6535 .- 1879-1298. ; 90:9, s. 2388-2395
-
Journal article (peer-reviewed)abstract
- Hydroxylated polybrominated diphenyl ethers (OH-PBDEs) along with methoxylated polybrominated diphenyl ethers (MeO-PBDEs) have been frequently identified as natural compounds in marine environment and also assumed as metabolites of PBDEs. In the present study, nine OH-PBDE, nine MeO-PBDE and 10 PBDE congeners were studied in the sewage sludge collected from 36 municipal wastewater treatment plants (WWTPs) in 27 cities of China. The results suggest that OH-PBDEs and PBDEs are ubiquitous in sewage sludge in China, however, methoxylated PBDEs were not detectable. Composition profiles of detected OH-PBDE congeners were different depending on the sampling location. ΣOH-PBDEs in WWTPs sludge ranged from 0.04 to 2.24 ng g-1 dry weight (mean: 0.35 ng g-1 dry weight). The total amount of the two most prominent congeners (6-OH-BDE-47+2'-OH-BDE-68) accounted for about 53.3-100% of the sum of all six identified congeners. A significant linear relationship was found between 6-OH-BDE-47 and 2'-OH-BDE-68. A distinct geographical distribution of ΣOH-PBDEs was observed with greater concentrations of OH-PBDEs at coastal areas than inland regions in China.
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39. |
- Wang, Pu, et al.
(author)
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Sources and environmental behaviors of Dechlorane Plus and related compounds : A review
- 2016
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In: Environment International. - Oxford, United Kingdom : Elsevier. - 0160-4120 .- 1873-6750. ; 88, s. 206-220
-
Research review (peer-reviewed)abstract
- Although Dechlorane Plus (DP) has been used as a polychlorinated flame retardant for almost half a century, its detection in the environment was not reported until 2006. The subsequent intensive research has confirmed its global ubiquity. A few reviews have presented the properties, analytical methods and environmental occurrence of DP and related compounds in the past several years. The present review emphasizes on the environmental behavior of DP isomers which is assessed by the variation of the isomer ratio of DP in various matrices. Other aspects including the analytical methods, emission sources, general environmental occurrence and bioaccumulation of DP are also summarized.In this review, three typical emission sources in the environment are categorized after introducing the measurement method of DP. The temporal-spatial distribution is then evaluated at the global scale, which provides an integrated representation of the environmental occurrence of DP and potential impact on the human health and ecosystems. The variations of DP isomer ratio in various matrices reinforce its source related distribution and their stereoselective bioaccumulation. Thereafter, DP related compounds and dechlorinated analogs are briefly summarized in regards to their occurrence in various matrices, suggesting their ubiquity in the environment and bioavailability. Further studies are required to better assess the exposures and toxicological effects of DP and its analogs. A special concern is the serious contamination in e-waste recycling areas in developing countries, where long-term monitoring data on the association of DP exposure and adverse effects to human health and ecosystems is urgently needed.
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40. |
- Wang, Thanh, 1979-, et al.
(author)
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Levels and distribution of polybrominated diphenyl ethers in the aquatic and terrestrial environment around a wastewater treatment plant
- 2016
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In: Environmental Science and Pollution Research. - Heidelberg, Germany : Springer. - 0944-1344 .- 1614-7499. ; 23:16, s. 16440-16447
-
Journal article (peer-reviewed)abstract
- The distribution and fate of polybrominated diphenyl ethers (PBDEs) in a riparian ecosystem nearby a wastewater treatment plant effluent were investigated. Different aqueous and terrestrial samples such as soil, sediment, plants, and invertebrates were collected and analyzed for tri- to heptabrominated PBDEs. Furthermore, the food web structure was elucidated using stable carbon and nitrogen isotopes. The highest PBDE levels were found for sediment- and soil-dwelling invertebrates, such as earthworms (Σ13 PBDEs 144 ng/g lipid weight), Tubifex tubifex (77 ng/g lw), and scarab larvae (49 ng/g lw). Differences in congener composition profiles among the different matrices show that the environmental distribution and fate of PBDEs in ecosystems can be very complex. Among the analyzed PBDEs in this ecosystem, the tetra-brominated BDE-47 was the dominant PBDE congener and followed by the penta-brominated BDE-99. A potential trend of increasing BDE-47/99 ratio with the increase of δ(15)N was observed for species with similar energy sources (δ(13)C), indicating a higher bioaccumulation potential for BDE-47 in this ecosystem. A significant correlation was also found between PBDEs and polychlorinated biphenyls (PCBs), indicating similar sources and fate between the two compound groups in this area. The biota-soil or biota-sediment accumulation factors (BSAFs) were somewhat different among the PBDE congeners and species, but were generally highest for those with log Kow values around 6.5-7.
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41. |
- Wang, Thanh, 1979-, et al.
(author)
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Levels of short chain chlorinated paraffins in pine needles and bark and their vegetation-air partitioning in urban areas
- 2015
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In: Environmental Pollution. - : Elsevier. - 0269-7491 .- 1873-6424. ; 196, s. 309-312
-
Journal article (peer-reviewed)abstract
- Short chain chlorinated paraffins (SCCPs) have been of considerable concern in recent years due to their high production volumes, environmental persistency and potential for long range atmospheric transport. Vegetation can take up considerable amounts of semivolatile organic compounds from the atmosphere and can act as indicators of local contamination. Paired pine needles and bark were sampled around Beijing during winter and summertime to investigate the distribution of SCCPs in urban areas. Levels in bark samples ranged 5.79-37.5 mu g/g on a lipid normalized basis (lw) with a geometric mean (GM) of 16.9 mu g/g lw whereas levels were 3.03-40.8 (GM 11.8) mu g/g lw for needles. Average congener group abundance profiles showed equal contribution of all four carbon groups (C10-13) in wintertime whereas higher abundances of C-10 and C-11 groups were found during summer. Uptake of SCCPs occurred mainly via kinetically limited gaseous deposition and particle bound deposition in the investigated area.
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42. |
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43. |
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44. |
- Wang, Thanh, 1979-, et al.
(author)
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Spatial distribution and inter-year variation of hexabromocyclododecane (HBCD) and tris-(2,3-dibromopropyl) isocyanurate (TBC) in farm soils at a peri-urban region
- 2013
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In: Chemosphere. - : Elsevier. - 0045-6535 .- 1879-1298. ; 90:2, s. 182-187
-
Journal article (peer-reviewed)abstract
- Hexabromocyclododecane (HBCD) is a high production volume brominated flame retardant (BFR) which has been of increasing environmental and public health concern due to its potential environmental persistency, bioaccumulation and toxicity. Tris-(2,3-dibromopropyl) isocyanurate (TBC) is another BFR which has recently been found in environmental matrices near a manufacturing plant, but its production volume and environmental distribution is currently not well known. This study was conducted to investigate the presence and distribution of these two BFRs in farm soils at a region in southeast Beijing. Total HBCD levels ranged from 0.17 to 34.5 ng g-1 on a dry weight basis (dw) with a median level of 2.97 ng g-1 dw. The composition profile of HBCD diastereoisomers was, on average, 28%, 13% and 59% for α-, β- and γ-HBCD, respectively. Detection frequency of TBC was only 25% in 2010 but was detected in all soil samples in 2011, and the median level was 0.19 ng g-1 dw with the range between below detection limit to 1.62 ng g-1 dw. There were no significant differences of HBCD and TBC levels among different irrigation sources in the region. The soil HBCD and TBC levels in samples collected in 2011 were significantly higher than in 2010. The increasing short-term temporal levels in farm soil might be due to the rapid urbanization in this region or could also reflect the increasing usage of HBCD and TBC after the phase out of other BFRs.
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45. |
- Wang, Thanh, 1979-, et al.
(author)
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Summer-winter concentrations and gas-particle partitioning of short chain chlorinated paraffins in the atmosphere of an urban setting
- 2012
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In: Environmental Pollution. - : Elsevier. - 0269-7491 .- 1873-6424. ; 171, s. 38-45
-
Journal article (peer-reviewed)abstract
- Short chain chlorinated paraffins (SCCPs) are semi-volatile chemicals that are considered persistent in the environment, potential toxic and subject to long-range transport. This study investigates the concentrations and gas-particle partitioning of SCCPs at an urban site in Beijing during summer and wintertime. The total atmospheric SCCP levels ranged 1.9-33.0 ng/m(3) during wintertime. Significantly higher levels were found during the summer (range 112-332 ng/m(3)). The average fraction of total SCCPs in the particle phase (ϕ) was 0.67 during wintertime but decreased significantly during the summer (ϕ = 0.06). The ten and eleven carbon chain homologues with five to eight chlorine atoms were the predominant SCCP formula groups in air. Significant linear correlations were found between the gas-particle partition coefficients and the predicted subcooled vapor pressures and octanol-air partition coefficients. The gas-particle partitioning of SCCPs was further investigated and compared with both the Junge-Pankow adsorption and K(oa)-based absorption models.
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46. |
- Wang, Thanh, 1979-, et al.
(author)
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Use of scalp hair as indicator of human exposure to heavy metals in an electronic waste recycling area
- 2009
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In: Environmental Pollution. - : Elsevier BV. - 0269-7491 .- 1873-6424. ; 157:8-9, s. 2445-2451
-
Journal article (peer-reviewed)abstract
- Scalp hair samples were collected at an electronic waste (e-waste) recycling area and analyzed for trace elements and heavy metals. Elevated levels were found for Cu and Pb with geometric means (GMs) at 39.8 and 49.5 microg/g, and the levels of all elements were found in the rank order Pb > Cu > Mn > Ba > Cr > Ni > Cd > As > V. Besides Cu and Pb, Cd (GM: 0.518 microg/g) was also found to be significantly higher compared to that in hair samples from control areas. Differences with age, gender, residence status and villages could be distinguished for most of the elements. The high levels of Cd, Cu and Pb were likely found to be originated from e-waste related activities, and specific sources were discussed. This study shows that human scalp hair could be a useful biomarker to assess the extent of heavy metal exposure to workers and residents in areas with intensive e-waste recycling activities.
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47. |
- Wang, Yawei, et al.
(author)
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Assessment of polychlorinated biphenyls and polybrominated diphenyl ethers in Tibetan butter.
- 2010
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In: Chemosphere. - : Elsevier BV. - 0045-6535 .- 1879-1298. ; 78:6, s. 772-777
-
Journal article (peer-reviewed)abstract
- The Tibetan plateau is considered a potential cold trap for persistent organic pollutants (POPs) and plays an important role in the global long-range transport of these compounds. This present work surveyed the concentrations of polychlorinated biphenyl (PCBs) and polybrominated diphenyl ethers (PBDEs) in Tibetan butter samples collected from different prefectures in Tibet autonomous region (TAR). summation operator(25)PCB concentrations ranged from 137 to 2518 pg g(-1) with a mean value 519 pg g(-1), which were far lower than those in the butter from other regions in the world. The highest level was found in butter from Sichuan province, which is located to the east of the Tibetan plateau and the lowest value was in samples from southeast TAR. The average concentration of summation Sigma(12)PBDE was 125 pg g(-1). The sample with highest and lowest summation Sigma(12)PBDE concentration (955 and 18.0 pg g(-1)) was from the south and southeast part of the plateau, respectively. Back trajectory model implied that the sources of these two groups of POPs were by atmospheric deposition in south, whereas the western plateau was mainly influenced by the tropical monsoon from south Asia. Air currents from Sichuan and Gansu province are further responsible for the atmospheric transport of PCBs and PBDEs to the eastern and northern side of the plateau. Local air concentrations of summation Sigma(5)PCBs predicted using air-milk transfer factor were at the lower end of published global levels.
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48. |
- Wang, Yawei, et al.
(author)
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Distribution of perfluorooctane sulfonate and other perfluorochemicals in the ambient environment around a manufacturing facility in China
- 2010
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In: Environmental Science and Technology. - : American Chemical Society (ACS). - 0013-936X .- 1520-5851. ; 44:21, s. 8062-8067
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Journal article (peer-reviewed)abstract
- Perfluorinated compounds (PFCs) can be released to the surrounding environment during manufacturing and usage of PFC containing products, which are considered as main direct sources of PFCs in the environment. This study evaluates the release of perfluorooctane sulfonate (PFOS) and other PFCs to the ambient environment around a manufacturing plant. Among the nine PFCs analyzed, only PFOS, perfluorooctanoic acid (PFOA), and perfluorohexane sulfonate (PFHxS) were found in dust, water, soil, and chicken eggs. Very high concentrations of PFOS and PFOA were found in dust from the production storage, raw material stock room, and sulfonation workshop in the manufacturing facility, with the highest value at 4962 μg/g (dry weight) for PFOS and 160 μg/g for PFOA. A decreasing trend of the three PFCs concentrations in soils, water, and chicken eggs with increasing distance from the plant was found, indicating the production site to be the primary source of PFCs in this region. Risk quotients (RQs) assessment for surface water >500 m away from the plant were less than unity. Risk assessment of PFOS using predicted no-effect concentration (PNEC, 3.23 ng/g on a logarithmic scale) indicated no immediate ecological risk of a reduction in offspring survival. PFOS concentrations in most egg samples did not exceed the benchmark concentration derived in setting a reference dose for noncancer health effects (0.025 μg/(kgxd)).
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49. |
- Wang, Yawei, et al.
(author)
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Quantitative structure-activity relationship for prediction of the toxicity of polybrominated diphenyl ether (PBDE) congeners
- 2006
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In: Chemosphere. - : Elsevier BV. - 0045-6535 .- 1879-1298. ; 64:4, s. 515-524
-
Journal article (peer-reviewed)abstract
- Levels of Polybrominated diphenyl ether (PBDEs) are increasing in the environment due to their use as flame retardants. The similarities of structure to polychlorinated biphenyl (PCB) congeners suggest that they may share similar toxicological properties, such as hepatic enzyme induction. In this work, quantitative structure-activity relationship (QSAR) models were constructed based on 406 descriptors for the logarithm of toxicology index (aryl hydrocarbon receptor relative binding affinities, AhR, I) of 18 PBDE congeners. The method used for building model is the Heuristic method, which is included in comprehensive descriptors for structural and statistical analysis (CODESSA) software. The best regression model involved four descriptors, which were related to the conformational changes, atomic reactivity, molecular electrostatic field, and non-uniformity of mass distribution in a molecule of PBDEs, etc. The high square of the correlation coefficient R(2)(0.903) showed the model was satisfactory.
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50. |
- Xie, Wenjing, et al.
(author)
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Unexpected Dioxin Formation During Digestion of Soil with Oxidizing Acids
- 2023
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In: Environmental Science and Technology. - : AMER CHEMICAL SOC. - 0013-936X .- 1520-5851. ; 57:39, s. 14717-14725
-
Journal article (peer-reviewed)abstract
- Dioxins, such as polychlorinated dibenzo-p-dioxins and polychlorinated dibenzofurans (PCDD/Fs), are among the most toxic unintentionally produced persistent organic pollutants, and their emission is of great concern. Herein, we discovered abundant dioxin formation in soil and various organic carbon-containing matrices after digestion with aqua regia. Sigma 17PCDD/Fs concentrations were in the range of 66.6-142,834 pg/g dw (5.6-17,021 pg WHO2005-TEQ/g dw) in 19 soil samples after digestion with aqua regia for 6 h. Sigma 17PCDD/Fs concentration was significantly and positively correlated with soil organic carbon content (R-2 = 0.89; p < 0.01). Compared with cellulose and lignin, humic acid served as an important organic matter component that was converted to PCDD/Fs during soil digestion. Strong oxidation and production of reactive chlorine by aqua regia may be the key factors in the formation of PCDD/Fs. The yearly emission of PCDD/Fs due to digestion with strong acids by the inspection and testing industry was estimated to be 83.8 g TEQ in China in 2021 based on the highest level, which was similar to 0.9% of the total dioxin inventory in China. Great attention should be paid to unexpected dioxin formation during digestion processes considering the potential risk of release from laboratories and enterprises.
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